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Last Modified 2021-09-16 14:14 EDT

(View included 12.0-U5.0 changes)

TrueNAS Quality Lifecycle

Release StageCompleted QA CyclesTypical Use-caseDescription
ALPHA1TestersNot much field testing
BETA2EnthusiastsMajor Feature Complete, but expect some bugs
RC3Home UsersSuitable for non-critical deployments
RELEASE4General UseSuitable for less complex deployments
U15Business UseSuitable for more complex deployments
U2+6+Mission CriticalSuitable for critical uptime deployments

August 17, 2021

iXsystems is pleased to announce the general availability of TrueNAS 12.0-U5.1! This is a performance improvement release that includes middleware updates for disk management operations. This release builds on all the bug fixes and quality of life improvements from the TrueNAS 12.0-U5 release.

With TrueNAS 12.0-U5.1, users will notice improved responsiveness with storage pool operations. This improvement applies to every kind of TrueNAS deployment, but those deployments with larger disk counts will see the greatest benefit.

TrueNAS CORE and Enterprise users are encouraged to upgrade their systems to get these latest performance improvements. Enterprise customers can contact iX Support for assistance with upgrading their TrueNAS systems.

Contact MethodContact Options
TelephoneMonday - Friday, 6:00AM to 6:00PM Pacific Standard Time:

US-only toll-free: 1-855-473-7449 option 2
Local and international: 1-408-943-4100 option 2
TelephoneAfter Hours (24x7 Gold Level Support only):

US-only toll-free: 1-855-499-5131
International: 1-408-878-3140 (international calling
rates will apply)

TrueNAS 12.0-U5.1 Changelog


  • NAS-111868 - Improve performance of middleware pool management

Known Issues

Asigra Plugin UpgradesAsigra users running version or earlier requires a TrueNAS CLI upgrade procedure to update to a new plugin version. In the TrueNAS web interface, open the **Shell** and enter iocage upgrade asigra-plugin-name, replacing asigra-plugin-name with whatever unique name was created for the plugin.
NAS-106992Persistent L2ARC is disabled by default.While the underlying issues have been fixed, this setting continues to be disabled by default for additional performance investigation. To manually reactivate persistent L2ARC, log in to the TrueNAS Web Interface, go to System > Tunables, and add a new tunable with these values:
  • Type = sysctl
  • Variable = vfs.zfs.l2arc.rebuild_enabled
  • Value = 1
TrueNAS "root" user account cannot be an SMB user.This is an intentional change to improve software security and suitability for deployment in a variety of environments. Update the SMB configuration to use a different user account.